A Study on Cable-Stayed Bridges Bahareh Bannazadeh 1,a , Zahra Sadat Zomorodian 2,b Mohammad Reza Maghareh 3,c 1 MA Student, Architecture Dept., School of Art and Architecture, Shiraz University, Shiraz, Iran 2 MA Student, Architecture Dept., School of Art and Architecture, Shiraz University, Shiraz, Iran 3 Asst. Prof., Architecture Dept., School of Art and Architecture, Shiraz University, Shiraz, Iran a bbbbanazadeh@gmail.com, b mazomorod66@gmail.com, c maghareh@shirazu.ac.ir Keywords: cable arrangement, cable-stayed bridge, long span Abstract. Cable-stayed bridges can be recognized as a suitable solution for connecting wide-span crossings. More than 600 cable bridges are constructed in the world till now while this process is in progress and this number is increasing. The span of cable bridges is between 100m to 500m wide usually while length of widest cable bridges has increased up to 1000m during this decade. Construction of such bridges still is so profitable and according to this point studying these bridges seems so important. Cable-stayed bridges are studied from many aspects such as number of spans, number of towers, number of cables and girder types. Among this process, this paper has gathered more than 100 cable stayed bridges around the world in a table and has assessed them based on different parameters and has categorized these bridges in 3 categories of harp, fan and radial. This categorizing has been based on a relationship between the pattern of cables and the width of spans. Fundamentals of this categorizing have been defined in the first step of this paper. In continue the results have been represented. At the end the relationship between the width of span of these bridges and the category will be analyzed and the final conclusion will be presented. Introduction The reason of popularity of contemporary cable-stayed bridges among bridges can be attributed to: 1) the appealing aesthetics; 2) the full and efficient utilization of structural materials; 3) the increased stiffness comparing with suspension bridges; 4) the efficient and fast mode of construction; and 5) the relatively small size of the bridge elements [1]. Cable-stayed bridges are structural systems which are effectively composed of cables, main girders and towers. A bridge carries vertical loads mainly by the girder. The staying cables provide intermediate supports for the girder so that it can cover a long distance. The basic structural form of a cable-stayed bridge includes a series of overlapping triangles comprising the pylon (or the tower), the cables, and the girder. All these members are under predominantly axial forces, with the cables under tension and both the pylon and the girder under compression. Axially loaded members are generally more efficient than flexural members [2]. As the most recent researches show, there are more than 1000 cable-stayed bridges in the world and this number is increasing rapidly. The span length has also increased significantly. Cable-stayed bridges are generally considered advantageous for spans between about 100m to 500m; however, larger spans over 1000m wide are not uncommon too [3]. Cable-stayed bridges can be distinguished by number of spans, number of towers, girder type, number of cables, etc. and based on structural systems, they are usually classified in five groups: 1) Cable-stayed bridges with curved decks, 2) Cable-stayed bridges without backstays, 3) Extra dosed bridges, 4) Giscard bridges and 5) Multiple-span cable-stayed bridges [4]. One hundred and three cable bridges all around the world have been defined by internet searching. Some important data such as year of construction, geographical region, main span, number of spans, bridge length and cable patterns are assessed. The cases were classified into three groups including: harp, fan and radial (Fig.1). Then each group of samples was provided in a Applied Mechanics and Materials Vols. 193-194 (2012) pp 1113-1118 Online available since 2012/Aug/24 at www.scientific.net © (2012) Trans Tech Publications, Switzerland doi:10.4028/www.scientific.net/AMM.193-194.1113 All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of TTP, www.ttp.net. (ID: 178.173.137.61-25/08/12,09:00:16)